cross ratio

A camera calibration method with co-line points is proposed, in which distortion center is located according to cross ratio invariability, and then distortion coefficients are calculated based on a line's central projection is a line.

提出一种用共线点列标定摄像机镜头畸变参数的方法，先根据交叉比不变性确定畸变中心，再利用直线的中心投影仍为直线这一性质确定畸变系数。

The geometric characteristics of 2D symmetric objects' in perspective images are lucubrated. The cross ratio of four lines is applied to describe feature points on object silhouette.

深入分析了2D对称性目标透视成像的几何特点，将共点四线交比用于目标轮廓上的关键点的特性描述中；

Cross ratio and element at infinity are two important concepts with projective geometry and primary tools in considerate projective property of figures.

交比和无穷远元素是射影几何中的两个重要概念，它们是探讨图形射影性质的主要工具。

In the second stage, the one order radial distortion parameter is computed by using cross ratio invariability.

根据透视投影的交比不变性解算一阶径向畸变参数；

The variation of the partial ionization cross section ratio versus the electron collision energy gained from spectrums is compared with experimental results obtained by K.

由此得到的部分电离截面积比对电子碰撞能量的依赖关系与K。

Isomeric cross section ratio for the~ ( 197) Au ( n, 2n) reaction at 15 MeV is measured by the activation method.

用活化法测量了15MeV中子引起~（197）Au（n，2n）反应的同质异能素截面比。

This paper presents a detailed analysis to the physical meaning and calculation formula for the main parameters of nonlinear distortions in amplifier: cross modulation ratio, 2nd order cross modulation ration and 3rd order cross modulation ratio.

本文详细地分析了放大器非线性失真的主要参数&交扰调制比，二阶、三阶载波互调比的物理意义和计算公式，并由此推导出电缆电视系统的设计方法。

There will be the case that the points do not match but they have the same cross ratio when calculated the invariants using the cross ratio.

同时在利用交比作为不变量进行特征点的匹配，会出现误匹配现象，即实际上并不匹配的点交比值却相等。

The cross ratio invariance of interaction system

相互作用系统的交比不变性

Calculation of Cross Modulation Ratio of CATV System

CATV大系统交调比的计算

Cross modality ratio matching method

交叉感觉比率匹配法

Cross plot ratio of social security overall performance persistence analysis shows that the Social Security Fund as a whole do not exhibits the continued performance, instead it exhibits anti-transformation characteristics.

运用交叉积比率法对社保整体的业绩持续性进行分析，发现社保基金整体不但没有呈现出业绩的持续性，反而具有反转型的特点。

Evaluation of Snell Experiments& Average Fission Cross Section Ratio of Equilibrium Spectrum in a Natural Uranium

评价Snell实验&大块天然铀介质中平衡谱的平均裂变截面比

The isomeric cross section ratio of~ ( 45) Sc ( n, 2n)~ ( 44g+ m) Sc

~（45）Sc（n，2n）~（44g+m）Sc反应的同质异能素截面比

Algorithm of space plane parameters based on cross ratio invariance

基于交比不变性的空间平面参数算法

A new calibration method of structured light system using a coplanar object is proposed based on invariance of cross ratio.

在交比不变原理基础上，提出了基于共面靶标的线结构光标定方法。

Systematics of Isomeric Cross Section Ratio for Neutron Induced Reactions

中子反应同质异能态截面比的系统学

A group of projective invariants was derived based on the cross ratio of five coplanar points, and used to recognize planar polygons. Experimental results show that the invariants have projective invariance and can be used to recognize planar polygons effectively.

利用共面五点的交比，导出一组用于识别平面多边形的射影不变量，用这组不变量实现平面多边形的识别，实验结果表明，这组不变量具有射影不变性，可以有效地识别平面多边形。

The Definitions of Cross Ratio of Four Lines in a Line Pencil

线束中四直线交比定义的讨论

The cross ratio he called anharmonic ratio.

他把交比叫作非调和比.

Systematics of Isomeric Cross Section Ratio for Proton-induced Reactions at E_n < 3 GeV

E p

Measurement of isomeric cross-section ratio

同质异能素截面比的测定与研究

On The Cross-Product Ratio of Log-linear Model

对数线性模型的叉积比诠释

Uncertainty Analysis of Constructing Calibration Points Based on Invariance of Cross Ratio A new approach for lens distortion calibration is presented, which utilizes the cross ratio invariability of perspective projection.

交比不变获取标定点的不确定性分析在分析目前的畸变参数标定方法优缺点的基础上，提出了一种能克服现有技术缺点的简单快速的镜头畸变参数标定方法。

Choice of the Best Cross Section Area Ratio of Gating System for Malleable Iron Pipe Fittings

玛钢管件浇注系统最佳断面比例的选择

It overcomes the disadvantages of existing distortion calibration approaches. Assumed only with one order radial distortion, image coordinates of only 4 special collinear points are needed as well as the cross ratio of them.

该方法利用了透视投影中的交比不变性质，在畸变模型为一阶径向畸变的情况下，只需要空间共线的4个点的图像坐标和其交比，建立一元二次方程即可标定畸变参数。

At the same time the feature point coordinates on the planar target were achieved with cross ratio invariability theory, then structured light parameters was calibrated.

同时利用交比不变性原理获取平面靶标上的特征点坐标，完成了结构光平面参数的标定。

The cross ratio of rational quadratic b-spline curves

比斜法有理样条插值有理二次B样条曲线的交比性质

Then, combining a flexible arm measuring machine and a standard ball with space round fitting algorithm, the presented model parameters are calibrated. Also, based on principle of cross ratio invariance, a fast calibration approach is presented. 4.

使用柔性臂测量机结合空间球拟合、空间圆拟合算法对检测系统测量模型参数进行标定，同时提出了一种基于空间几何交比不变性原理的检测系统测量模型参数快速求解方法。

In the calibration of the system, a plan based on the principle of cross ratio invariance in algebraic projective geometry was used to calibrate the coded light planes.

在对编码投影光平面的标定过程中，提出利用代数射影几何中的交比不变原理对其进行标定的方案，并论述了标定原理。